1. Field of the Invention
This invention relates generally to a weather strip for mounting relative to a door opening in an automobile so as to provide a seal between the door opening and an associated automobile door, and more particularly to such a weather strip having a corner portion having an improved sealing effect.
2. Prior Art
FIGS. 4 to 6 show one conventional weather strip 1 to be mounted on a periphery of a door opening in an automobile as shown in FIG. 1. This conventional weather strip comprises a body including a trim portion 11 of a U-shaped cross-section for fitting on a peripheral flange 3 on the door opening, a hollow seal portion 12 with which a door 20 of the automobile is adapted to be sealingly engaged, and a sealing lip 13 formed on a distal end of one arm of the U-shaped trim portion 11 for being sealingly engaged at its distal end or edge with a surface defining the door opening.
The weather strip body comprises two straight elements 1A and 1B of extruded rubber and a corner element 1C of molded rubber interconnecting the straight elements 1A and 1B at their one ends and molded integrally therewith. The reason for the use of such molded corner element 1C is that if the weather strip body is made solely of an extruded element, the seal portion 12 is deformed at a corner portion C (FIG. 1) of the door opening to such an extent that the sealing effect is adversely affected.
For joining two extruded straight elements 1A and 1B of the weather strip body together through the corner element 1C, generally, one ends of the two elements 1A and 1B are placed in a cavity of a mold in generally perpendicular relation to each other, with a core inserted in the mold cavity. Then, a molding material is poured into the cavity, that is, a space defined by the cavity surfaces and the core to form a corner element 1C interconnecting the two straight elements 1A and 1B and molded integrally therewith. After this molding operation, the mold is removed, and then an opening is formed in the corner element 1C to remove the core therefrom. Therefore, the resulting corner element 1C has a core-removing opening 2.
Conventionally, the core-removing opening 2 is provided in the inner side of the curved portion of the corner element 1C, and an adhesive or the like is applied to the edges of the opening 2 to bond them together to close the opening 2 after the core is removed from the molded corner element 1C.
When the core-removing opening 2 is closed in this manner, the seal portion 12 of the corner element 1C is radially contracted into a smaller cross-section as indicated in broken lines at 12' in FIG. 6. Thus, this seal portion 12 is reduced in size, and therefore there is a risk that its sealing effect is affected. Further, the core-removing opening 2 is exposed to an external view when the weather strip 1 is mounted on the automobile, which detracts from the appearance.